This is somewhat shorter than astronomers had estimated from ground-based observations.
These observations should be about ten times more precise than any ground-based observations.
At the same time, other dedicated programs focused on galaxies that were already known through ground-based observation.
A critical theoretical turning point was reached with ground-based observations in 1988.
However, due to heavy intervening absorption, ground-based observations for a long time failed to identify any of them.
In the early days of planetary geology, ground-based telescopic observations were all the data we had.
Moreover, recent technological advances have led to improved ground-based observations.
It is the first Kreutz-group comet discovered by ground-based observation in 40 years.
The two other rings had also been seen in ground-based observations, but they were too fuzzy and obscure for interpretation.
The first 3 planets listed were discovered by Kepler team members using ground-based observations.